OMAHA (DTN) -- With the U.S. Department of State expected to release its assessment of a newly proposed Keystone XL pipeline route through north-central Nebraska, environmental groups have started a full-court press to persuade the Obama administration to reject the pipeline, again.

The Natural Resources Defense Council released two reports Thursday aimed at showing the potential detriments of stepping up tar sands oil production with the completion of the Keystone pipeline. The group announced the reports' findings at a news conference held at the National Press Club in Washington.